Hold TMS high during reset.

This is a questionable fix for the Kinetis K22F that samples
this pin on release from reset to enable its EzPort which
makes the flash unusable and disables the rest of the micro.

src/platforms/native/platform.c

@@ -176,6 +176,7 @@ void platform_init(void)
 
 void platform_srst_set_val(bool assert)
 {
+	gpio_set_val(TMS_PORT, TMS_PIN, 1);
 	if ((platform_hwversion() == 0) ||
 	    (platform_hwversion() >= 3)) {
 		gpio_set_val(SRST_PORT, SRST_PIN, assert);